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If you hang around Hackaday long enough, pretty soon you’ll start to see some patterns emerging. As the nexus of all things awesome in the hacking world, our front page offers a unique vantage point by which you can see what’s getting folks excited this particular month, year, or decade. Right now we can tell you hackers love the Raspberry Pi, 3D printing, and perhaps above all, they can’t get enough mechanical keyboards.

That being said, we can’t help but notice there’s a lot of open space inside the 3D printed enclosure. Right now there’s nothing inside but the Raspberry Pi, which only takes up a fraction of the internal volume. Adding a battery and hard drive would be the logical next steps, but it could also be outfitted with a suite of radios and various other hacking and security research accoutrements. We’ve seen an influx of such builds over the last few months, and the Jazzberry seems like it could make a very slick entry into this burgeoning category of mobile pentesting devices.

Follow this train of thought: cars have sensors, cars are in frequent use over large areas, cars are the ultimate distributed sensor network for weather conditions.

Many years ago, as I wasted yet another chunk of my life sitting in the linear parking lot that was my morning commute, I mused that there had to be a way to prevent this madness. I thought: What if there was a way for the cars to tell each other where slowdowns are? This was long before smartphones, so it would have to be done the hard way. I imagined that each vehicle could have a small GPS receiver and a wireless transceiver of some sort, to send the vehicle’s current position to a central server, which would then send the aggregate speed data for each road back to the subscriber’s car. A small display would show you the hotspots and allow you to choose an alternate route. Genius! I had finally found my billion dollar idea.

Sadly, it was not to be. Seemingly days later, everyone on the planet had a GPS-equipped smartphone in his or her pocket, and the complex system I imagined was now easily implemented as software. Comically, one of the reasons I chose not to pursue my idea is that I didn’t think anyone would willingly let a company have access to their location information. Little did I know.

Most of use read and comment on Hackaday from the desktop, while we let our mind work through the perplexing compiler errors, wait for that 3D print to finish, or lay out the next PCB. But more and more people discovering Hackaday for the first time are arriving here on mobile devices, and now they’ll be greeted with a better reading experience — we’ve updated our look for smaller screens.

Yes, it may be a surprise but there are still people who don’t know about Hackaday. But between featuring your amazing hacks, and publishing the incredible original content tirelessly written by our amazing writers and editors, we’re seeing more new readers than ever. Our mission is to bring hardware hacking and the free and open sharing of information and ideas to people everywhere. So we made a responsive design that fits on the tall and narrow shards of glass attached to everyone’s hand.

There’s a generation of mobile-first hackers that we know has been headed our way — just a few years ago I lamented the change this poses to full-sized keyboards. But we think everyone should be interested in the kind of delightful self-learning that happens all the time around here and we’re happy to improve the mobile experience for that reason. Now we look great on a cellphone screen, and continue to look great on your battlestation where you have one-tab-always-open with Hackaday while laying out that circuit board, or debugging those timing issues on a sweet embedded project.

[Nikola Tesla] believed he could wirelessly supply power to the world, but his calculations were off. We can, in fact, supply power wirelessly and we are getting better but far from the dreams of the historical inventor. The mainstream version is the Qi chargers which are what phones use to charge when you lay them on a base. Magnetic coupling is what allows the power to move through the air. The transmitter and receiver are two halves of an air-core transformer, so the distance between the coils exponentially reduces efficiency and don’t even think of putting two phones on a single base. Well, you could but it would not do any good. [Chris Mi] at San Diego State University is working with colleagues to introduce receivers which feature a pass-through architecture so a whole stack of devices can be powered from a single base.

Efficiency across ten loads is recorded at 83.9% which is phenomenal considering the distance between each load is 6 cm. Traditional air-gap transformers are not designed for 6 cm, much less 60 cm. The trick is to include another transmitter coil alongside the receiving coil. By doing this, the coils are never more than 6 cm apart, even when the farthest unit is a long ways from the first supply. Another advantage to this configuration is that tuned groups continue to work even when a load changes in the system. For this reason, putting ten chargeables on a single system is a big deal because they don’t need to be retuned when one finishes charging.

5G is gearing up to be the most extensive implementation of mesh networking ever, and that could mean antennas will not need to broadcast for miles, just far enough to reach some devices. That unsightly cell infrastructure stuck on water towers and church steeples could soon be hidden under low-profile hunks of metal we are already used to seeing; manhole covers. This makes sense because 5G’s millimeter radio waves are more or less line-of-sight, and cell users probably wouldn’t want to lose connectivity every time they walk behind a building.

At the moment, Vodafone in the UK is testing similar 4G antennas and reaching 195 megabits/sec download speeds. Each antenna covers a 200-meter radius and uses a fiber network because, courtesy of existing underground infrastructure. There is some signal loss from transmitting and receiving beneath a slab of metal, but that will be taken into account when designing the network. The inevitable shift to 5G will then be a relatively straightforward matter of lifting the old antennas out and laying the new hardware inside, requiring only a worker and a van instead of a construction crew.

Modern handheld gaming hardware is great. The units are ergonomic powerhouses, yet many of us do all our portable gaming on a painfully rectangular smartphone. Their primary method of interaction is the index finger or thumbs, not a D-pad and buttons. Shoulder triggers have only existed on a few phones. Bluetooth gaming pads are affordable but they are either bulky or you have to find another way to hold your phone. Detachable shoulder buttons are a perfect compromise since they can fit in a coin purse and they’re cheap because you can make your own.

[ASCAS] explains how his levers work to translate a physical lever press into a capacitive touch response. The basic premise is that the contact point is always touching the screen, but until you pull the lever, which is covered in aluminum tape, the screen won’t sense anything there. It’s pretty clever, and the whole kit can be built with consumables usually stocked in hardware stores and hacker basements and it should work on any capacitive touch screen.

Ok, there are some worthy laws in place regulating the sale and distribution of alcohol — and for good reason. For many a bootlegger, however, the dream of renovating an old trailer from 1946 into a mobile bar is a dream that must– wait, what? That already exists?

It’s no mobile workshop, but the bar was initially built to accommodate guests at their wedding. [HelloPennyBar] has shared the reconstruction process with the world. Inside, there’s everything you’d need to serve beverages, including a (double) kitchen sink. In addition to a water tank, a pair of car batteries serve as the central power with electrical work installed for interior lights, a small fan to keep the bartenders cool, exterior lights, a water pump, the trailer lights, and more exterior lights so the patrons can party the night away.

Before you say anything, [HelloPennyBar] says they would need a license to sell alcohol, but alleges that for serving alcohol at private events in their state it suffices to have an off-site responsible serving license. Furthermore, a few helpful redditors have chimed in regarding battery safety and cable-mounts, to which [HelloPennyBar] was amenable. Safety and legality noted, the mobile bar must make for a novel evening of fun.